Fast and deterministic

PX5 RTOS is extremely fast and efficient. On typical 32-bit microcontrollers running at 80MHz, most API calls and context switches complete in less than one microsecond. It’s also a deterministic RTOS: The processing for each API and context switch is completely predictable and not a function of the number of active threads. For example, the processing required to obtain a semaphore is the same whether two or 100 threads are active.
One of the smallest RTOS
This is one of the smallest embedded RTOSes, requiring less than 1KB of flash memory and 1KB of RAM on typical 32-bit microcontrollers. Implemented with loosely coupled C functions, RTOS size scales automatically based on the application's use. The linker does not bring APIs and associated functions into the image unless they are used.
Simple — two main source files
The RTOS is composed of two main source files: px5.c and px5_binding.s. Drop these RTOS files into any C main project example, and PX5 is ready to run. No complicated projects and/or linker control file changes.
Using PX5 in an application is also easy: Simply include POSIX pthread.h and add a call to px5_pthread_start to your C main function, as follows:
#include <pthread.h>
int main()
{
/* Start PX5. */
px5_pthread_start(1, NULL, 0);
/* Once px5_pthread_start returns, the C main function
has been elevated to a thread - the first thread in
your system! */
while(1)
{
/* PX5 RTOS API calls are all available at
this point. For this example, simply sleep for
1 second. */
sleep(1);
}
}
PX5 RTOS is easy to install and use, taking only a few minutes. Use the processor-to-tool binding layer examples as a starting point.
Native POSIX pthreads API support simplifies development.
- This Linux RTOS-compatible API reduces the learning curve for Linux developers new to embedded RTOS.
- POSIX-compatibility enables code sharing between devices that run embedded Linux.
Advanced technology
- Data encapsulation technology assists compilers in generating the smallest, fastest code and reduces namespace collision with the application.
- Pointer/Data Verification (PDV) technology, a next-generation embedded RTOS technology, enables unprecedented verification of run-time function pointers, linked lists, and stacks.
- Central error handling - with optional user enhancement - helps facilitate building more robust applications.
Full source code
- You receive complete source code, including the RTOS binding layer source.
- The RTOS source code is designed to be easily understood.
- The RTOS source code is rigorously tested: complete C statement and branch decision coverage testing for every release.
- Discover the highest quality RTOS source on the market.
PORTABLE RTOS
PX5 RTOS is written in ANSI C, making it highly portable to any processor architecture with C compiler support because 99%) of the RTOS is written in ANSI C. It supports popular embedded MCU and MPU architectures, including Arm Cortex-M, Cortex-R, Cortex-A, MicroBlaze, Renesas RX, RISC-V, TriCore architecture families.
IAR, Arm & GCC tool support
As with its processor support, the PX5 RTOS supports the most popular embedded development tools, including those from IAR, Arm, and GCC.
PX5 RTOS also provides a meaningful subset of C++17 multithreading support that is portable across all C++ development tools.
Royalty-free RTOS
PX5 offers royalty-free licensing for the PX5 RTOS. Like the product itself, the PX5 RTOS licensing is simple and easy to work with.
LicensingProfessional tech support
Always ready to help, the embedded RTOS experts on the PX5 support team promise quick action on every request. Unlike many open-source and some commercial RTOSes, RTOS support is available when you need it. We are here to help!
Support
Ask me about PX5 RTOS—its industrial-grade design, technical advantages, and why it’s trusted by embedded developers. 🚀